Question

For each call to the following method indicate what console output is produced
public void mysteryXY ( int x, int y) {
if ( y==1){
System.out.print(x);
}else{
System.out.print(x * y + " , ");
mysteryXY( x, y-1);
System.out.print(" , " + x * y);
}
}
mysteryXY(5,2)
mysteryXY(10,1)

Answer 1

Answer:

First call:

For the call mysteryXY(5,2)

First, mysteryXY is called with x=5 and y=2

As y is not equal to 1 , else part is executed:

First line of else block is:

System.out.print(x * y + " , ");

which prints 10 ,

Then second line of else block makes a call mysteryXY(5, 1)

As y=1 in this call, This call goes to if block and prints 5 , and control goes out of the function and back to the original call where x=5 and y=2

Then third line of else block is executed which prints , 10

Output:

Second call:

In the call mysteryXY(10,1) x=10 and y=1 , so it goes to the if block only and simply prints x

So,

10

output:

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